Rachis

Vertebral column or rachis (profile
view): bony axis of vertebrates, comprised of the set of vertabrae
from the base of the skull to the pelvis.5 fused vertebrae: the vertebrae that form the end of the spine,
the coccyx.Coccyx region: bone comprised of the fused, atrophied vertebrae
at the end of the sacrum.Sacral region: bone that is jointed with the hip bone to form
the pelvis.Lumbar region: the part of the spine in the area of the loins
(5 vertabrae).Thoracic region: the part of the spine in the area of the thoracic
cage (12 vertebrae).Cervical region: the part of the spine in the area of the neck
(7 vertebrae).